Electromagnet device.



I J. s. HODGES. ELECTROMAGNETIGDEVICE.

;Application filed Apr. 14, 1902.) (No Model.)

WITNESSES: /N VENTOH yaw WM Patented Dec. 2, I902.

2 Sheets-Sheet Na H4304 J.S.HODGE& ELECTROMAGNETIC DEVICE.

KApplicntion filed Apr. 14, 1902'.)

(No Model.)

Patented Dec. 2, I902.

2 Sheets-Sheet 2.

WITNESSES: INVENTOR- citing-current the release of the armature is changer or cnrrent-reverser UNITED STATES JAMES SHALER l-IODGES,

PAT NT OFFICE.

OF TROY, NElV YORK.

ELECTROMAGNETIC DEVICE.

SPECIFICATION forming part of Letters Patent No. 714,904, dated December 2, 1902.

Application filed April 14. 1902.

To all whom it may concern:

Beit known that 1, JAMES SEALER Honors, a citizen of the United States, residing at Troy, in the county of Rensselaer and the State of New York, have invented a new and useful Improvement in Electromagnetic Devices, of which the following is a specification.

My invention relates to that class of electromagnetic devices which are intended to perform the same function upon the passage of an operating-current in either-direction and whichshould continue to perform the same function during the time of reversal of the current, and has for its object maintaining the continuity of electromagnetic action during said time of reversal of current.

Of the above devices the so-called slowacting relay is a type, and I have selected it as adapted to show the principle 'underlying my invention, but I do not confine the scope of application solely to this or any other special type. As heretofore constructed, slowacting relays consist of an electromagnet with single magnetic circuit wound with one or more coils, and which when energized attract a movable armature, thereby controlling other apparatus. Duringreversal ot the exdelayed by mechanical or other means until the magnet has been denergized and again excited. There must, however, necessarily be an instant when no attraction is exerted by the poles on the armature-4. 6., there is a cessation of the action of the electromagnetic device. By embodying the principle of my invention in at all .times during the reversal of the exciting-current be an attraction between the armature and the electromagnet, as will be evident from the drawings and the following description.

In Figure l I have shown the form of electromagnet M which I prefer to use, consisting of a single yoke Y, armature D, and cores A A A On cores A and A are wound exciting-coils 0' 0 connected through the pole- E to battery 13. Figs. 2 and 3 show other forms which the dosuch a relay there will vice may take, and in Fig. 4 the form' shown in Fig 1 is shown applied to a signaling c1rl cuit for railways.

Serial No. 102,845. (No model.)-

Considering Fig. 1, the armature D is free to move on the pivot d and when attracted will close a local circuit through contact-point f, bell F, and battery G. The pole-changer E will when thrown over reverse the polarity of the circuit, including coils C and C and consequently the direction of the exciting currents. It is evident that the electromag- .net M has three magnetic circuits each comprising the yoke Y, armature D, and one air of cores A A or A and A or A and A, and that one or more of these magnetic circuits will be energized it there be any current flowing in either of the coils C orC, and that unless the currents in both coils are zero a pull will be exerted on the armature D. The coils Cand C are s proportioned that the time-constant o O is greater than that of C -that is, with the same conditions operating to reverse the currents that in C will require a longer time to change than that in C The operation will be as follows: Starting with the pole-changerEin the position shown, cnrrentis passing through both coils C and C and the armature D is held up. The polechanger when contacts first short-circuits the coils C and 0 by bridging the contactpoints a and o and then reverses thepolarity of the battery. The currents in C and C will not reverse instantly, but that in C will change at the greater rate, and consequently will pass through zero before that in C and will have reversed when that in C is passing through zero. By this means there will always be current in one or other of the two coils, and consequently an attraction between armature D and electromagnetM.

Figs). and 3 show two of the many forms in which the principle may be utilized. Fig. 2 shows two electromagnets M and M with separate armatures D and D, arranged to close a local circuit through the contact-points f or f when either or both armatures are attracted. In Fig. 3 are shown two electromagnets M M acting on the same armature and through its means closing a local circuit. The other letters in all three figures refer to parts which perform tions in each arrangement. cases the magnetic circuits are only two,

In these latter and the same fnne- 'lagtrack-circuit 3 and opening 65 tion of the device M and the value these separate; but if the constants of the coils C and C be so adjusted and the coils so connected that at least one of the said magnetic circuits is energized at every in- 5 ,stant during reversal of the total current the action of the device as a whole depends upon the principle 4 my invention.

In Fig. 1, I have shown the pole-changer E with the con tacts a,b,and carranged so that the circuit of the electromagnet M is not o ened, but is short-circuited momentarily as the pole-changeroperates. This is not, however, essential to successful operation, as the arrangement shown in Figs. 2 and 3 will produce the desired results, and it isimmaterial how the change in polarity is accomplished. The local circuit through fF G D shown may of course be replaced by any mechanism, electrical or otherwise, controlled by the armature. Any method known/to the art may be employed to adjust the time-constants of the coilsfor example, altering the resistance or the self-induction of the coils, inserting a condenser, or by the use of externalresistances, secondary coils, &c., or coils maybe wound on all three cores or more cores employed, with. coils or without, and various other arrangements-without departing from the principle of-my invention.

In Fig. 4 a device of the above description is shown in connection with an automatic block-signaling system with overlap. l 2 3 4 are four blocks of a track. of which blocks 2, 3, ands are protected by thesignals 62 63,64. The track-circuit 2 includes a bat tery 13, a pole-changer It, a polarized relay 72, and a neutral device M, constructed in accordance with my invention. When polarized relay 72 is energized by current in proper direction, which will be when device M isenergized,a local circuit is closed through contact-point S2, battery 92, and signal 62 thereby put clear. The neutral device M through its armature operates the polechanger, thereby controlling the direction of current from battery 10 in circuit 1, at

the further end of which are the same connectious as shown for block 2'. So in block 3 we have included in track circuit battery 14, pole-changer E polarized relay 73, neutral device M the last controlling pole changer E, and thereby the direction of current in track-circuit 2 and the action of polarized relay 72. At 5'is shown a pair'of wheels short-circuiting track-circuit 4 and denergizing polarized relay 7s and neutral device'M, the former putting signal 64 to danger and the latter reversing current in polarized relay 6073,50 putting signal 63 to danger. The

operation of the system may readily be fo lowed from the drawings, and it will be seen that blocks 2, 3, and 4 serve as overlaps for blocks 1, 2, and 3, respectively. The operaof my in vention will be seen when considering that as a train-passes out of block 4 the neutraldevice M is energized and the polarity oftrackcircuit 3 reverses, thereby through polarized relay clearing signal 63. The same operation reverses the direction of current in neutral device M and should its armature drop for an instant track-circuit 2 would be reversed, signal 62 would go to danger, and a similar failure on the part of device M would send a false danger indication back another block. If, however, M M, &c.. are constructed on the principle of my invention, their action will be continuous throughout the reversal of current,.and the indications of signals controlled by them will not be affected by a sudden change in polarity.

I do not confine the scope of application of the invention to the above system, asit is evident that its utility is equally great in connection with any system of signaling where two indications are to be given over one circuit, whether track or signal circuit. For instance, in a system protected by home and distant signals the pole-changer may be operated by the advance home and the polarized relay control the distant signal while the neu tral device controls the home. A little consideration wi ll'also show its application to normal danger, or. normal clear systems,while the polarized relaymay be replaced by any device responsive solely to current in one direction only in the track or signaling circuit.

Electromagnetic devices with delayed action have been produced and are in use, but none of them depend for their action 0 causing the magnetization of the various parts'of the device so to change that there is no time during the change from positive to negative excitation when every part is demagnetized.

What I therefore claim, and desire to se: cure by Letters Patent, is

1. An electromagnetic device adapted to produce a unidirectional effect while the exciting current varies from a positive to a negative maximum, and comprising electric circuits of different time-constants and a -plnrality of magnetic circuits, suchmagnetic circuits being controlled by such-electric circuits.

2. An electromagnetic device having electric circuits of different time-constants and aplurality of magnetic circuits, such magnetic circuits being controlled by such electric circuits, in combination with means for reversing the polarity of such device.

3. An electromagnetic device comprising a plurality of electric circuits and a plurality of magnetic circuits, each magnetic circuitinterlinked with one or more of the electric circuits,

such circuits having different time-constants so that all of the magnetic circuits are not demagnetized at the same instant while the to-' tal operating-current varies from a positive to a negative maximum.

4. An electromagnetic device comprising a plurality of electric circuits and a plurality of magnetic circuits, each magnetic circuit interlinked withone or more of the electric circuits,

such circuits having different time-constants so that all of the magnetic circuits are not demagnetized at the same instant while the total operating-current varies from a positive to a negative maximum, in combination with means for reversing the polarity of such device.

5. An electromagnetic device comprising a plurality of electric circuits having different time-constants, and a plurality of magnetic circuits, each magnetic circuit interlinked with one or more of the electric circuits, in combination with means for reversing the po- 'larity of the device.

6. An electromagnetic device having exciting-coils of different time-constants and magnetic parts constructed to form a plurality of magnetic circuits under the control of such coils, in combination with means for'reversing the direction of current flowing through such coils.

7. An electromagnet consisting of three cores or limbs of magnetic material in magnetic contactwith one another at one end, and at the other each presenting aLfree end, and exciting-coils wound on two of said limbs or cores; said coils having difierent electromagnetic time-constants. v V

8. In combination, an electromagnet con- 3o sistingo'f three cores or limbs of magnetic material iu magnetic contact with one another at one end, and at the other each presenting a free endfiand exciting-coils wound on two limbs; and a single armature so disposed as to be attracted when current flows in either or both said exciting-coils.

9. An electromagnetic device comprising three cores of magnetic material in magnetic contact with one another at one end and at the other end each presenting a free end, and exciting coils of different time-constants wound on two of said cores, in, combination with a pole-changer constructed to reverse the direction of current flowing through such coils.

-10. An electromagnetic device comprising exciting-coils having different time-constants and magnetic parts constructed to form a pinrality of magnetic circuits under the control of such exciting coils, a source of electric energy, and a pole-changer controlling the flow of current from the source of electric energy to the exciting-coils and constructed to effect the reversing movement withoutopening the circuit of the sourceof electric energy by short-circuiting the exciting-coils during the reversing movement.

JAMES SHALER HODGES.

Witnesses.

J onn FERGUSON, 0. H. TOLHUNT. 

